反应详情

To a stirred solution of diisopropylamine (14.22 ml, 101.43 mmol) cooled to −78° C. is added dropwise butyllithium (60 ml). The reaction mixture is stirred and allowed to warm to 0° C. over 15 minutes after which time 2-chloro-4-methylpyridine is added to the stirred solution. After 1 hour, ethyl acetate (18.88 ml) and THF (78 ml) are added over 45 minutes followed by acetic acid (11.4 ml, 193.2 mmol) and stirring continued for 20 minutes. The reaction mixture is concentrated in vacuo and the crude product dissolved in with water (200 ml). The aqueous is extracted with chloroform (3×300 ml) and the combined organic portions washed with water (200 ml), brine (200 ml), dried over MgSO4 and the solvent removed in vacuo to yield the crude product as a brown oil. Purification by chromatography on silica, eluting with ethyl acetate-hexane affords the titled compound.

1. additionis added to the stirred solution
2. stirringstirring
3. waitcontinued for 20 minutes
4. concentrationThe reaction mixture is concentrated in vacuo
5. dissolutionthe crude product dissolved in with water (200 ml)
6. extractionThe aqueous is extracted with chloroform (3×300 ml)
7. washthe combined organic portions washed with water (200 ml), brine (200 ml)
8. dry with materialdried over MgSO4
9. customthe solvent removed in vacuo
10. customto yield the crude product as a brown oil
11. customPurification by chromatography on silica
12. washeluting with ethyl acetate-hexane